No. Though they are designed to attach metal to metal they're also used to attach metal to wood fiberglass and plastic. Sheet metal screws are fully threaded with a sharp point.A pre-drilled hole is required for installation.
Joining is accomplished by the solvent cementing process or hot air welding methods. (Callout Designation S-PVC0111 per ASTM D6263). PVC Angle is available in Grey, White & Clear.